Parametric GIS and HBIM for Archaeological Site Management and Historic Reconstruction Through 3D Survey Integration

Abstract

This study presents a practical methodology for integrating the multiscale spatial information of archaeological sites by combining Geographic Information Systems (GISs) with Historic Building Information Modelling (HBIM). The methodology categorises and integrates data based on its type and geometric scale, leveraging advanced 3D surveying techniques alongside semantic and parametric modelling tools. A multiscale system is proposed to manage heterogeneous geospatial data efficiently, enabling the development of enriched geometric models with detailed semantic and parametric attributes. The effectiveness of this approach is demonstrated through a case study of the Archaeological Area of Ancient “Abellinum”, showcasing seamless integration between HGISs and HBIM across multiple levels of detail. This work highlights the potential for enhanced management and the interpretation of archaeological heritage using innovative digital methodologies, highlighting the importance of representation in documenting historical transformations.

1. Introduction

1.1. Methods and Tools for Cultural Heritage Management

The integration of Geographic Information Systems (GISs) and Building Information Modelling (BIM), particularly in its disregard for historical heritage, Historic Building Information Modelling (HBIM), represents a transformative approach to the documentation, conservation, and management of cultural heritage. By combining the spatial analytical capabilities of GISs with the geometric and semantic details of HBIM, this integration offers a holistic framework for multiscale analysis and interdisciplinary collaboration. Recent technological advances have made smooth transitions between these platforms possible, as demonstrated by using methodologies that convert Industry Foundation Classes (IFCs) from BIM into CityGML for GISs, ensuring data consistency across different levels of detail [1].

GISs and BIM were initially developed for distinct purposes: GISs were developed for spatial and urban management and BIM was developed for architectural design and construction processes. Although the complementary strengths of these technologies have driven research towards increasing interoperability, in the context of cultural heritage, it is possible to maintain them as separate tools while exploiting their peculiarities. A GIS is ideally suited to the representation of the spatial context and the understanding of macroscopic dynamics. At the same time, HBIM focuses on the detailed modelling of specific sites, focusing on conservation, degradation, and monitoring phenomena [2]. The parallel use of both is of fundamental importance for the professionals involved in the virtual reconstruction of the history of cultural heritage.

GISs, for example, can be used to explore and analyse the integration of ancient cities into the contemporary urban texture, the relationship between hydrography, orography and historical settlements, and the strategic positioning of communication routes. These tools allow one to explore a site’s spatial configuration of the surrounding landscape, facilitating an understanding of the historical and natural context [3].

On the other hand, HBIM permits a detailed representation of individual buildings or urban agglomerations, providing precise information on material conditions, such as the deterioration of plasters, the preservation of decorative features and the monitoring of structural phenomena. These three-dimensional models, enriched with multidimensional information, support restoration planning and maintenance management. By keeping GISs and HBIM separate, their specific analytical capabilities are enhanced. A GIS is used to study the spatial context at a larger scale, and HBIM is used for more detailed representations at a local scale, creating a synergy that offers an integrated and layered view of cultural heritage. This approach, which combines macro- and microscopic analyses, supports a more conscious and sustainable management of historic assets. Today, the trend is to converge towards using a single multiscale geodatabase for both Geographic Information Systems and Building Information Modelling, thus enabling interoperability between different professional actors, such as engineers, architects, restorers, and archaeologists, each operating at various scales.

This integrated approach has a significant advantage: it concentrates all relevant information into one platform, facilitating interdisciplinary dialogue and ensuring a comprehensive and coordinated view of cultural heritage. However, this strategy also entails some challenges. On the one hand, the inherent complexity of such systems can be an obstacle for individual actors who are less familiar with specific information tools [4]. On the other hand, there is the risk of overloading the database with redundant or inconsistent data, compromising the effectiveness of analyses and decisions. It is, therefore, crucial to adopt clear management protocols and data standardisation strategies to maximise the benefits of these multiscale platforms. Ultimately, GISs and HBIM, when used in synergy and with a structured approach, offer a powerful tool to understand and manage cultural heritage in an integrated way, balancing the needs of local detail and spatial context. This integration offers a unique opportunity to strengthen the sustainability and preservation of our historical heritage by addressing today’s challenges with advanced digital tools. In particular, adopting multisensor digital technologies for land and archaeological surveying, combined with a multidisciplinary approach, is crucial for tackling future challenges in protecting and enhancing cultural heritage.

This article specifically focuses on applying GIS and HBIM methodologies—kept separate and not integrated—to the archaeological area of ancient Abellinum, located in Atripalda, in the province of Avellino. The aim is to demonstrate how GISs and HBIM can support the management of archaeological data even while keeping the two separate, offering new opportunities for the conservation, restoration, and enhancement of historical assets. At the end of the discussion, it will be demonstrated that the methodology employed has also allowed for the verification of the historical phases of the transformations of the building under study, enabling the creation of probable virtual reconstructions across different time periods.

1.2. Landscape Archaeology: Advanced Tools for Studying and Managing Heritage

Landscape archaeology is a discipline that applies archaeological principles to systematically study the interactions between human communities and their natural and built environments over time. This approach enables the analysis of archaeological sites and architectural structures as material evidence, revealing valuable insights into the evolution of landscapes, construction techniques, and the socio-cultural context in which they developed. One of the fundamental tools in this field is stratigraphic wall analysis, which helps identify different construction phases and subsequent interventions, reconstructing the chronological sequence of events that shaped the built environment. Advanced techniques, such as photogrammetry and laser scanning, provide detailed and accurate representations of structures, facilitating conservation and restoration efforts.

In the literature, numerous studies have demonstrated the value of integrating\GIS (Geographic Information System) and HBIM (Historic Building Information Modelling) for digitising and managing archaeological sites. This combination has proven particularly effective for documenting, analysing, and preserving cultural heritage, dealing with the complexities of multiscale representation, and managing heterogeneous data [5]. This approach also supports digital historical reconstructions (e.g., those that are useful for storytelling or engaging visitors in the historical evolution of a building). There are several scientific studies that offer a significant example, who developed a methodology to integrate geomatic data and historical information in GISs and HBIM. For example, Tsilimantou et al. [5], in their study conducted on Villa Klonaridi in Athens, used three-dimensional surveys and multisensory analysis to create models enriched with information on the building materials and the state of preservation of the building. This approach allows for the monitoring of degradation and the planning of more effective restoration interventions. Another significant contribution is that of Dore and Murph [6], who developed a workflow to integrate HBIM models within a 3D GIS through the CityGML framework. The approach, applied to historic sites in Ireland, combines architectural details with geographical data, improving the management and analysis of historic buildings. The ability to exploit parametric objects and a semantic framework has enhanced the documentation and preservation of these sites.

Bruno et al. [7] present Chimera, a web-based system that integrates and manages HBIM and GIS data in a single platform. This system enables the representation and analysis of information at different spatial and temporal scales, as demonstrated in the case study on the historic city of Parma. The approach allows for linking data from various epochs, thus supporting evolutionary analyses and restoration decisions.

Pepe et al. [8] explore GIS-HBIM integration for multiscale representations in historic centres. The study focused on the city of Popoli and shows how the combined use of GIS and HBIM models allows for the historical and architectural context to be documented in detail, facilitating restoration planning and vulnerability assessments. The methodology uses CityGML and HBIM models enriched with semantic and parametric information. These studies highlight the great potential of integrating GISs and HBIM into cultural heritage, offering advanced tools to address complex challenges. However, interoperability and data complexity management issues also emerge, requiring further research to optimise these integrated approaches and make them more accessible and practical. The approach—which until the last decade was exclusive—of a GIS for the documentation of cultural heritage is highlighted by the Open platform of the “National Archaeological Geoportal (GNA)” [7], which allows for the sharing of archaeological survey data, thus promoting knowledge and valorising cultural heritage.

A GIS has also been applied in various internationally significant contexts, such as studying the medieval castle of Palaiokastro in Greece. Here, the combined use of terrestrial laser scanners and UAVs allowed for the creation of detailed 3D models and the analysis of the site’s topographic configuration, identifying different construction phases and supporting the planning of conservation interventions [9]. Another important example is the study on the historic centre of Popoli (Abruzzo), which combines GISs and HBIM for multiscalar representations (LOD), integrating UAV surveys, laser scanners, and historical documents. This methodology supports conservation, urban planning, and the sustainable management of cultural heritage.

The study on the Temple of Antas in Sardinia uses HBIM by combining SfM surveys and algorithmic modelling to reconstruct the temple’s geometry accurately. This approach supports the management of architectural complexities and the preservation of archaeological heritage [10]. Finally, the project for Chan Chan in Peru leveraged satellite imagery and GISs to plan an archaeological park [11]. The GISs enabled the georeferencing of archaeological data, the monitoring of site degradation, and the proposal of a buffer zone to protect the site from urban expansion. This multidisciplinary integration effectively supported the management and enhancement of the archaeological complex, once again demonstrating the value of GISs in preserving cultural heritage. Parallelly, Historic Building Information Modelling (HBIM) represents a significant advancement in the study of archaeological landscapes.

By integrating data from advanced surveys, such as photogrammetry and laser scanning, HBIM enables the creation of detailed digital models of existing structures. For instance, the documentation project for Villa Rufolo in Ravello utilised an integrated workflow combining photogrammetric and laser scanner surveys to produce a parametric model. This model, enriched with historical and technical data, is a systematic repository to support future restoration and maintenance decisions [12]. In the archaeological site of Pompeii, an HBIM methodology documented stone pavements through digital elevation models, generating detailed three-dimensional representations enriched with material data [13,14]. On a larger scale, at the Valentino Castle in Turin, a combination of point cloud segmentation and parametric modelling was employed to create an accurate HBIM of the historic structures. Semi-automatic tools supported the modelling of unique elements, such as vaulted ceilings and irregular masonry, improving information management and enabling stratigraphic analysis and long-term conservation [15]. The integration of high-density, georeferenced geometric data with high-quality colorimetric detail, combined with historical information and field investigations (e.g., archaeological excavations and/or ground-penetrating radar surveys), can generate a comprehensive dataset [15]. This dataset serves as a foundation for digitally recreating, albeit virtually, the ancient splendours of the past [16,17].

The tools outlined above demonstrate significant potential in enhancing and reconstructing assets that have undergone extensive transformations throughout their long history. In Figure 1, the workflow adopted by the authors for the geometric analysis and historical reconstruction of the case study is presented. It is important to emphasise that this workflow is inherently flexible and can be further refined or expanded during the historical research phase, the on-site survey, as well as during modelling and the association of informative parameters in the database.

1.3. The Project: Abellinum

The “Abellinum” project (“Abellinum. Piano per la conoscenza, la tutela e la valorizzazione dell’antico centro irpino”), developed in Atripalda (Avellino, Italy), represents an innovative example of an application of 3D Survey Multi-Data Integration in the field of landscape archaeology. Led by the Department of Cultural Heritage Sciences/DiSPaC of the University of Salerno (prof. A. Santoriello), beginning in 2019, it takes place in collaboration with the Soprintendenza Archeologia, Belle Arti e Paesaggio for the provinces of Salerno and Avellino, the Direzione Regionale Musei Nazionali Campania, and the Municipality of Atripalda (AV). It includes the participation of the Department of Civil Engineering (DiCiv) for the surveys and representation of the area, the support of the ICT Centre for Cultural Heritage for innovative solutions and services of enhancement and enjoyment, and the Department of Pharmacy (DIFARMA) for the analysis of the vegetal and environmental heritage. Archaeological research and excavations are authorised by Ministerial Concession (MIC_DG-ABAP_SERV II 01/06/2022. 0020738-P [34.61.07/1.27.1/2019]—DG ABAP|31/05/2022| DECRETO 696). The project aims to study the ancient city of Abellinum and the surrounding area, a territory of great historical and strategic importance since the Samnite and Roman ages. The methodology adopted integrates data from different disciplines, including geomorphology, botany, remote sensing, and archaeological analysis, to create an Integrated Knowledge System managed in a GIS environment for the macro scale and BIM systems for the detailed scales. This system aims to expand the knowledge of the archaeological heritage and provide tools for protecting and enhancing the cultural context, understood as a Cultural Ecosystem [18,19,20]. The ancient centre of Abellinum, located in the Civita area of Atripalda, occupies a plateau of about 25 hectares near the confluence of the Rigatore stream with the Sabato River (Figure 2). The strategic position, exploiting the river valley and the road networks, guaranteed connections with the Tyrrhenian and Adriatic coasts. Born as a Samnite oppidum, it became a Roman colony between the end of the 2nd and the beginning of the 1st century BC, with a defensive system in opus quadratum (4th-3rd century BC) that was later replaced by a fortification in opus reticulatum (1st century BC), and is about 2 km long with towers and city gates [21,22,23]. Beginning from the 1st century BC, the settlement acquired an organic urban structure with a central public area, which today has been damaged by the so-called Guanci quarry. To the west, buildings such as a cryptoporticus and a cardo, known from excavations in the 1960s and 1970s, are no longer visible. To the east are the best-preserved structures, such as the public baths and other monuments that are accessible to the public [24]. To the northeast, the archaeological remains are distributed along the decumanus, an east–west road that remained in use until the city’s final phases, likely in the 6th–7th centuries AD (Figure 3). To the north of the road stands the domus of Vipsanius Primigenius, which provides the context for applying the methodology described in this contribution. To the west of the domus, the excavations have brought to light the continuation of the decumanus towards the public area and two buildings overlooking the roadway (Figure 3A—investigations into the National Geoportal for Archaeology (GNA—https://data.d4science.net/GKAi (accessed on 01 March 2025)). The building to the south is indicated by two partially excavated rooms, which are open to the road and seem to have served functions related to production activities in the Late Antiquity. The space investigated is still too small to be able to propose a more detailed hypothesis. Still, the presence of a small canal with a small collection basin and traces of a hearth or, more likely, of a fire point, with ash and metal waste, pushes towards this interpretation. The building is located near a road crossroads originating from the decumanus and a cardo, and this space was probably enriched by a fountain, in which the small pillar with the face of a river deity remains.

Another building has been identified on the northern front of the decumanus; in this case, too, the excavation is still ongoing, and at present, it is composed of at least ten rooms that have undergone planimetric variations and renovations following the eruption of Pollena in 472 AD. If, in the Late Imperial age, the complex was configured, due to its plan and distribution of rooms, as another domus, after the eruption there are records of the razing of wall partitions and the construction of new walls that attest to a rearrangement of the spaces for residential and, perhaps, productive activities.

To the east of the domus, beyond the cardo, the excavation operations have brought to light the succession of some rooms and a large open area (Figure 3B). Inside the rooms, cocciopesto floors and remains of plaster on the walls have been recognised. The structures, built with various construction techniques, seem to lead back, based on the planimetric organisation observable so far, to another domus or to a residential unit. The phases of occupation of the Imperial age have been brought to light, observing how this part of the building was uninhabited in the middle of the 5th century AD when the Pollena eruption occurred (472 A.D.). On the eastern side, a large open area is delimited by a wall and, beyond, by beaten earth floors, probably relating to a passage space that borders the block. The domus of Vipsanius Primigenius, built beginning in the Late Republican and Augustan periods, represents one of the few structures that was extensively investigated in the 1970s (by G. Colucci Pescatori and M. Fariello Sarno) and in 2008–2009 (by S. Quilici Gigli) both from a planimetric and diachronic point of view [25,26,27,28].

The investigations have allowed us to reconstruct the building’s different construction and maintenance phases, which evolved over time through progressive expansions until it became a rich residence with typical characteristics of “terrace” houses. The plan for the building features rooms decorated with frescoes, making the domus a unique example of Roman domestic architecture. Its plan is structured on the succession of atrium and peristyle, with the entrance on the decumanus to the south, and the rooms demonstrating a functional axial distribution. The entrance (vestibule and tetrastyle atrium) leads to the living and reception area, characterised by the tablinum and the peristyle, with a natatio, a sort of small pool. Rooms (oeci) frescoed with various decorative motifs [29] open onto this porticoed space; there are triclinia and two cubicula close to the northern side of the house. The domus survived until the 3rd century AD and was subjected to restoration and reconstruction starting from the 4th century AD, also following seismic events (the earthquake of 346 AD); only the southern parts, which continued to gravitate along the decumanus, were progressively used throughout the Late Antiquity period until their final abandonment.

2. Materials and Methods

2.1. Integrated 3D Survey Techniques

TLS (Terrestrial Laser Scanning) and photogrammetric techniques have advantages and disadvantages; the project budget becomes decisive rather than the required objectives or the level of detail. Photogrammetric techniques require experience, especially acquisition, to obtain an accurate final result. TLS, on the other hand, although easy to use, requires experience in setting the parameters and is costly and time-consuming. The choice of method to use mainly depends on the complexity of the site to be investigated, the accuracy requirements, and the budget and time available. For this reason, integrating multiple techniques is often the most suitable solution. The initial purpose of the survey campaign was the documentation for its subsequent valorisation of the entire archaeological area of Abellinum; therefore, a reality-based model of the ancient city and its surroundings was acquired using integrated survey techniques to serve as a basis for those dissemination activities aimed at promoting the Italian cultural heritage. The integrated survey, obtained by combining UAV and TLS data, was performed to fill the gaps of both clouds, consisting of large portions of the ancient city that had not been surveyed due to the thick vegetation [30]. Therefore, the resulting three-dimensional multiscale model was suitable for developing detailed HBIM models and an initial assessment of possible maintenance and restoration works. To obtain complete coverage of the area under examination, a UAV survey was planned to be also integrated with TLS once they had been registered within the same coordinate system through six common control points. The acquisitions obtained in this way, therefore, provided an accurate and georeferenced database for the subsequent HBIM phase of the domus of the archaeological area of Abellinum.

2.1.1. The Unmanned Aerial Vehicle (UAV) 3D Survey

Due to the relevance of the case study and to create a texture that would be usable in future applications, an aerophotogrammetric survey with advanced technical characteristics was planned. The survey was conducted using a DJI Mavic 2 Pro drone (Manufacturer: DJI, City: Shenzhen—China), equipped with an integrated 20-megapixel camera, with a 1-inch CMOS sensor, a resolution of 5472 × 3648 pixels, a field of view of 77 degrees, a focal length of 8.8 millimetres, and a pixel size of 2.41 micrometres. Image processing was performed using the commercial software Agisoft Metashape version 2.1.1. The georeferencing of the point cloud, within the EPSG area of 32633—WGS 84/UTM 33N, was performed using six ground control points (GCPs) measured in nRTK (network real-time kinematics) mode via an Emlid Reach RX receiver (Manufacturer: Emlid, City: Saint Petersburg—Russia). The control point measurement accuracy was maintained within 1.5 centimetres in both planimetry and altimetry, with an overall error of fewer than 2.5 centimetres. The flight plan was designed using DJI Ground-Station version 1.4.63, with 314 photogrammetric shots arranged according to a square grid for nadir images. A total of 318 images were acquired, with an average Ground Sample Distance (GSD) of approximately 2.5 centimetres per pixel, covering a total area of approximately 25 hectares. The photogrammetric process was processed in the Agisoft Metashape environment, setting the quality to “Maximum” and deactivating the filters. At the end of the processing, the survey produced a dense point cloud composed of over 82 million points, a mesh with more than 20 million faces and about 10 million vertices, and a texture with a size of 8192 pixels.

2.1.2. The Terrestrial Laser Scanning (TLS) Survey

The laser survey campaign was carried out employing a phase-distance laser scanner, the Faro Focus S150 plus (Manufacturer: FARO Technologies, Inc., City: Lake Mary, Florida—USA), with an integrated GNSS receiver and an HDR integrated camera, which, under optimal environmental conditions, provides a scanning range of 0.6 m to 150 m, a measurement speed of up to 2.000.000 points/s, a linearity error of ±2 mm, a vertical FOV of 300°, and a horizontal FOV of 360°. The instrument was set to acquire scans with an average resolution of 1/5 with a quality of 3×. A total of 10 TLS stations were set up along the Roman domus case study perimeter, with an average density between 100 and 350 points/dm². In fact, the survey with the TLS had the aim of integrating the lack of photogrammetry data for the domus, particularly under the plexiglass covering protecting the archaeological remains.

Proprietary Faro Scene 2020 software—version 2020.0.4.5330 (8.0.4.5330)—was used for data processing. The structured, registered information was later exported to the Autodesk ReCap environment—version 2024.0, where the GCPs previously measured were also used to georeference the laser point cloud to proceed to import the photogrammetric cloud within the same project and the same reference system.

Figure 4 illustrates the distinction between point clouds generated using range-based and image-based technologies and their subsequent integration through georeferencing. This process enabled the combination of photogrammetric data from drone flights with laser scanner data captured beneath the canopy, protecting the domus. The resulting unified point cloud provides a comprehensive visualisation, including masonry details that were not captured solely through UAV photogrammetry.

2.1.3. Close-Range Photogrammetry for Mosaic Orthophotos Wall

To complement the previously acquired three-dimensional data and create an information repository for monitoring decorated walls, a close-range photogrammetry survey was conducted specifically on walls with plaster or mosaics within the domus. This technique was used to survey 17 internal walls, with the aim of producing precision orthophotos of the facades.

The ultimate goal is to project these orthophotos onto the HBIM model, making them accessible for interactive visualisation and as virtual links. These tools will facilitate the long-term monitoring of the potential deterioration or degradation of the walls, providing an effective resource for the conservation and management of architectural heritage. To generate the wall orthophotos, approximately 540 images were captured, with an average of 32 images per wall. The average Ground Sample Distance (GSD) for each wall was less than 0.5 cm, ensuring a high level of detail.

The camera used for all close-range acquisitions was a Nikon D3100 (Manufacturer: Nikon Corporation, City: Tokyo—Japan), equipped with a CMOS sensor measuring 23.1 × 15.4 mm, a 25 mm focal length lens, a crop factor of 1.56, and a pixel size of approximately 5 µm. It is worth emphasising that, through the georeferencing of the point cloud acquired via TLS and its integration with the same acquisition of the environments, each orthophoto containing decorative elements was accurately georeferenced and scaled. This process was achieved using natural GCPs that were easily identifiable on the walls, such as edges, stains, or colour variations.

The point clouds derived from close-range photogrammetry were not included in the integrated cloud intended for the subsequent Scan-to-BIM phase. Instead, the close-range images were used to generate high-definition orthophotos, primarily for documenting the current state. These orthophotos will later be projected onto the parametric elements of the HBIM model’s vertical surfaces for enhanced representation and analysis.

2.2. GIS Platform

From the very start, the Abellinum project has adopted a multi-perspective approach. Historical, archaeological, geological, and geomorphological analyses are being combined to uncover settlement patterns, agrarian cadastral systems, and ancient infrastructure, including road networks. This transdisciplinary methodology has naturally produced a vast amount of highly heterogeneous data (from a spatial, quantitative, and qualitative point of view).

One of the project’s primary goals has been to create an effective system for managing these data. The system had to not only ensure the preservation of information but also make it easy to visualise, share, and process for research purposes. To meet these needs, a geospatial database was developed using QGIS, an open-source GIS platform. This decision reflects the project’s commitment to accessibility and adaptability. The wide range of data and goals—spanning scientific research, heritage conservation, and public engagement—has required a multiscalar approach. This method, which is essential for studying ancient landscapes, involves working at various levels of detail to address different aspects of the research [31,32,33].

The analyses operate at three interconnected levels:

• The Macro Level examines the entire territory of ancient Abellinum, focusing on the Sabato River valley at its heart. This broader perspective combines geographical and cultural criteria to investigate the region’s geomorphology, settlement history, and the ancient landscape. Key sites identified through archival and bibliographic research are mapped as points in QGIS, and they have been catalogued thanks to a specially created table. This attribute table is organised into different sections: anagraphic aspects (ID, province, municipality, toponym, source, references), spatial and material aspects (definition, spatial reliability, surface, height), chronological aspects (chronology, chronological reliability, periodisation), and descriptive and interpretative aspects (description, interpretation). This makes it possible to carry out detailed analyses and queries based on selected fields and specific parameters. When available, excavation plans and site maps are georeferenced and represented as polylines, offering insights into the orientation and layout of structures. The GIS environment has also been populated with a number of other elements in an ESRI shapefile format drawn from both past and ongoing research related to primary and secondary road forms, hydraulic infrastructure (e.g., the Augustan and Samnite aqueducts), and agricultural subdivision schemes. All these elements fit on a heterogeneous cartographic base in raster formats, consisting of geological maps, DTM (with a resolution from 25 m to 1 m), different thematic maps obtained from the regional GIS website, i.e., IGM 1:25,000, as well as the hydrographic network in ashapefile format. The study conducted on this type of scale allowed for relating to Abellinum without considering it as an isolated entity but dropped into a specific territorial context. With a view to proceeding to the reconstruction of the ancient landscape, an attempt has been made to focus attention not only on the individual sites listed but also on the relationship between them over time and, above all, on the dynamics existing between man and the environment, also going on to investigate the connective tissue formed by the “empty” spaces existing between the sites, within which ancient communities lived and carried out their activities (Figure 5).

• The Intermediate Level shifts the focus to the Abellinum site itself, analysing its layout and how it connects to the broader territory. However, those spaces located in the immediate vicinity of the plateau are also taken into consideration, as they were intended for different functions in ancient times (burial areas, craft areas, entertainment areas) and directly connected to the life of the colony. Also in this case, a census of the evidence was carried out and its positioning in GISs, in the form of point and linear geometries. In the same geodatabase are added the results of different research activities, like ortophotos from drones, geophysical (georadar and geomagnetic) data from multiple surveys, and morphological features individuated both from field analysis and from the elaboration of detailed LIDAR data [34]. All of these data contributed to the reconstruction of the ancient landscape of the plateau (and its surroundings), which in ancient times must have presented greater heterogeneity from an altimetric point of view. The positioning of archaeological evidence was fundamental for the stratigraphic excavation planning activities (started in 2021) and for the research conducted on the urban organisation of the ancient city. It was decided to position all the data from archaeological research in GISs, including the often generic information collected by scholars and antiquarians of the past, as well as by contemporary enthusiasts and people who still live on site today, establishing a greater and lesser reliability criterion for each element. All this made it possible to define an extremely valuable database for research but also, in fact, an updated archaeological map, functional for protection and preventive archaeology activities. This level bridges the wide-scale regional analyses with the fine details explored at the micro level. Always operating on a medium scale, the activity carried out by the DiFarma (UNISA) team was also of great importance, which proceeded to the census and mapping of every plant species present on the Civita. This operation proved to be important in order to understand the status of local species and to become aware of the threats posed by alien and invasive species, both towards local flora and archaeological structures. (Figure 6).

• The Micro Level delves into specific archaeological contexts, focusing on excavation data and the reconstruction of individual features or areas within the site. As regards the aspects related to GISs, the inter-site scale approach is adopted mainly for the aspects connected to archaeological research in the field, in particular to archaeological excavation. This methodology has long been the standard practice in archaeological research activities and is also essential to comply with ministerial standards. Through the techniques of stratigraphic excavation, the survey activity via GNSS, total station and photogrammetry, and the study of the materials coming from the excavation itself, it is possible to have a representation in a GIS environment of the single stratigraphic unit, accompanied by a specifically structured attribute table containing all the main information (Figure 7). The attribute table created for stratigraphic units is different from the one described above for regional sites. It contains synthetic information related to descriptive aspects (ID number, typology, dimensions, height, findings) and excavation methods (technique, year of excavation, drawer).

While microscale operations conducted through GISs have become a traditional element in archaeological studies, the Abellinum project offers a different approach to this level of detail, represented by the adoption of the HBIM methodology, which is applied in the case study submitted here. In this context, BIM has been employed not only for the as-built modelling of the current state of the site but also to propose a virtual reconstruction based on archaeological and structural research (as-reconstructed BIM) by integrating historical data and archival research [35]. In this case, the BIM model constitutes an important product for archaeological research on the Abellinum site and for the enhancement and dissemination of its cultural value.

2.3. Scan-to-BIM Architectural Modelling

An HBIM model was created based on the architectural and geometric documentation obtained through interdisciplinary and multiscale work. This model, as is well known, relies on parametric modelling aimed at digitising existing heritage assets of historical value, utilising a methodological approach that promotes the integrated and collaborative management of digital twins for artefacts of significant historical and architectural importance [36]. Following the established Scan-to-BIM practice, the adoption of HBIM is grounded in a rigorous, multi-phase methodology that integrates the skills and tools described in the previous sections [36]. Each process phase ensures an accurate three-dimensional representation of historical buildings and the effective management of the associated information. The first phase, consisting of data collection through advanced surveying techniques, also includes in-depth research into the architectural rules and history of the analysed artefacts. This step is crucial for understanding the historical and cultural context in which the buildings were conceived and constructed and ensuring an accurate virtual reconstruction of their architectural details. Subsequently, the HBIM methodology involves the creation of a library of parametric objects and components based on the architectural rules identified in the previous phase. In this specific case, the library was oriented toward reconstructing the geometric configuration of spaces that no longer exist, adopting a comparative approach.

The construction of the HBIM model for the digital twin was implemented to allow for continuous enrichment with geometric and informational data about the entire building and its individual architectural and structural components. Describing the parametric object library features helps to understand the project’s complexity. For example, during the development of the HBIM model, specific architectural rules were identified that allowed the creation of custom parametric elements (for example, the columns of the peristyle for “Phase 1”) that were not available in the BIM software used.

In the case of the domus modelling, the parametric model was developed using Revit software (Autodesk Revit, San Rafael, CA, USA, 2018, version 2024). Some material properties, such as the flooring details, were integrated using the software’s existing libraries of parametric objects. However, the ontology of most elements of the historical building was created by integrating information from a multidisciplinary analysis of the documentation. The final phase of the HBIM parametric modelling process focuses on the automated extraction of graphical and informational documents for the analysis and documentation of the studied buildings. These documents provide a detailed representation of the architectural and historical features of the buildings and serve as a valuable resource for scholars and professionals working in cultural heritage conservation.

3. Results

3.1. Geometric Documentation

To create a digital twin of the domus, a “subtractive” strategy was adopted. The comparative modelling system employed aimed to reconstruct the entirety of the domus based on available archaeological data and comparisons with contemporary artefacts sharing a common cultural and technical matrix. This approach also included hypothesising the configuration of the roof system, which no longer exists [37]. This methodology was chosen not only to produce a study model capable of serving as a repository for historical and archaeological information for documenting and managing the artefact but also to simplify the modelling process, particularly for the above-ground structures [38].

For load-bearing linear structures and floors, the modelling process started with the point cloud survey of the intervention area, leading to the creation of various types of construction elements. For walls, these were classified according to their construction type and thickness, leveraging the capabilities of the BIM platform. Dimensional calibration, including the linear extension and width of elements, was performed manually based on the point cloud. Regarding height dimensions, the bases of the walls were anchored to insertion levels, while their tops were aligned with upper levels, with their measurements cross-checked against hypotheses made during the study and research phase.

Given the uniqueness and specificity of the domus of Abellinum, where no parallels could be drawn with objects in the software libraries, custom modelling was required. Each real element was discretised into its constituent parts. In particular, the columns of the atrium and peristyle were analysed, with each identified type decomposed into its base, shaft, and capital. Individual profiles were modelled and reassembled into nested families that were meaningful and recurrent. This solution proved especially effective as it allowed for the detailed representation of each component while reconstructing the whole as a semantically significant element within the broader syntax. Moreover, thanks to parametric modelling, the adopted approach can be easily adapted to create similar digital objects by manipulating the same parametric matrices to produce varied geometric configurations. However, in this specific case, since all the columns were modelled identically, no further parametrisation was needed beyond the initial iteration (Figure 8).

To reflect the archaeological ruin state of the walls and columns as they exist today, a subtractive modelling workflow was implemented. Starting from the model created based on the point cloud, elements that were no longer present in the current state were selectively removed. However, since the model serves as a unified representation of all the temporal phases of the domus, it was not feasible to simply delete elements, as this would remove them from the overall model. To address this, geometric subtraction was achieved using “void” objects, parametric volumetric entities that interact with solid hosts to create reversible and parametric subtractions of solid portions of the model.

To prevent temporal inconsistencies between different historical periods, a phase-based parametric organisation was employed using Revit’s integrated phase management tools. This organisation accounted for the three primary evolutionary phases of the domus: the Late Republican period, the Imperial period, and the current intervention state. Once these phases were defined and each model element was assigned to a specific phase, it became possible to select which elements to “demolish” in the current state.

3.2. Multidisciplinary Documentation Data and HBIM Creation: Reconstruction Hypothesis

A key focus of the project was the precise definition of construction phases, implemented using the “Project Phases” tool in Autodesk Revit. This methodology enabled the association of each model element with a specific temporal phase, distinguishing between the Late Republican phase, the Imperial phase, and the current state.

The volumetric modelling process commenced with the establishment of reference levels derived from the point cloud data obtained through advanced digital surveying techniques. Primary structural elements, including walls, floors, and roofs, were modelled using standard system families, whereas complex components, such as the peristyle columns, required the development of custom parametric families. This approach ensured a precise and architecturally accurate representation of the domus, reflecting its complexity and unique characteristics [39]. This classification facilitated the visualisation of structural transformations over time, delineating the architectural configurations that were specific to each historical period. The project enabled the documentation of the main construction phases, the formulation of reconstruction hypotheses, and the proposal of solutions for site conservation and valorisation. Archaeological evidence, corroborated by historical and documentary sources, identified three principal construction phases:

• Late Republican phase (“Phase 1”): This phase corresponds to the initial construction campaign centred on the atrium and the southern section of the domus. The original core exemplifies the atrium-style typology, featuring the vestibulum, cavum aedium, and impluvium. The construction techniques and proportions are consistent with Late Republican Roman residential architecture and align with Vitruvian principles.
• Imperial phase (“Phase 2”): This phase represents a significant architectural expansion, introducing the peristyle and surrounding rooms. The reconfiguration increased spatial complexity with the addition of representational spaces such as the alae and triclinium. The design proportions adhere to Vitruvian guidelines, underscoring the influence of De Architectura in shaping the domus’ architecture. With the onset of the crisis that brings a slow but steady depopulation of the Civita, the rooms of the domus cease to have a living and organic function, with them being split up, closed, and re-functionalised, and each one being destined for different production or storage activities; in this context, the conclusion of the domus’s living history can be identified.
• Current state (“Phase 3”): This phase captures the present condition of the domus, shaped by centuries of alterations, demolitions, and interventions. Excavation campaigns provided critical data for reconstructing the building’s evolutionary trajectory and documenting its current conservation state.

The development of the BIM digital model of the domus of Abellinum was a multidisciplinary and technically sophisticated process aimed at capturing both the historical evolution and the current state of the structure. By integrating high-precision digital surveys, archaeological analyses, and advanced parametric modelling methodologies, the project produced a comprehensive and scientifically robust model that consolidates and synthesises all available data (Figure 9). By integrating diverse data sources at varying scales, it was possible to propose virtual reconstructions of the domus across its main historical phases. Field investigations and historical information were crucial in aligning the key structural elements, ensuring consistency and accuracy in the proposed reconstructions. An example, shown in Figure 10, is the reconstruction of the domus during the Imperial era through the use of two-dimensional graphic elaborations and renders.

4. Discussion and Conclusions

The integration of BIM in archaeology continues to be in a developmental phase, offering significant potential for advancing digital practices in this domain. This study adopts a counter-trend approach by maintaining a distinction between BIM and GIS applications to optimise their respective strengths. The workflow begins with GISs for data collection, spatial analysis, and contextual understanding, progressing to 3D modelling to hypothesise and visualise the studied contexts. BIM is then employed to generate “intelligent” virtual reconstructions, where each component is interconnected and enriched with metadata, including detailed information about the hypothesis-driven reconstruction process.

While BIM models for archaeological reconstructions demonstrate promise, challenges remain, particularly in the parameterisation of objects, which differs from the standardised approaches used in BIM as-designed or as-built models. Similarly to HBIM, the standardisation of intricate geometries and unique architectural features continues to present obstacles. Although the IFC schema generally accommodates most elements, unique and complex architectural components often require manual modelling and semantic association with generic classes. A promising direction for future research involves extending the IFC standard (or developing a related derivative) specifically for historical and ancient architectural heritage, combined with the creation of shared object libraries—a concept that has long been advocated for in HBIM research [40].

In this context, the integration of multiscale representations and the intersection of diverse datasets—such as field investigations, historical research, and 3D surveys (range-based and image-based)—are fundamental. These datasets provide a critical foundation for analysing the interconnections between the various transformations of a historical building, allowing for the hypothesis and reconstruction of its temporal phases. Digital tools thus serve not only as visualisation instruments but also as verifiers, enabling geometric and functional assessments to validate hypotheses about historical evolutions.

The case study of Abellinum illustrates the partial complexity that is inherent in Roman construction techniques and architectural examples. Although this representation is not exhaustive, the proposed methodology establishes a foundation for advancing virtual archaeology. Here, the virtual environment transcends traditional visualisation to function as a “digital research laboratory”, enabling data analysis, simulations, and hypothesis testing. By integrating updates to the IFC standard, this framework could also support open-access models and seamless data exchange across platforms, ensuring broader dissemination and collaboration.

To further enhance the approach, the GIS project will incorporate additional excavation data from Abellinum, establishing a comprehensive knowledge base for stakeholders. The BIM system, leveraging its advanced capabilities, will support simulation and dissemination activities, advance research on this site, and contribute to the broader national archaeological heritage.

The BIM model serves as a springboard for achieving higher levels of detail. Its integration with IoT sensors installed within the domus offers future applications for structural monitoring and conservation planning. Moreover, BIM is currently being employed in research focused on the decorative elements of the domus, opening pathways for interdisciplinary studies.

In conclusion, the integration of GISs and BIM demonstrates the potential for synergies between these methodologies without imposing rigid frameworks. This approach emphasises the value of diverse-scale representations and the intersection of heterogeneous databases as indispensable tools for uncovering interconnections between transformations in historical structures. By leveraging modern digital tools, both geometric and functional validation processes are enhanced, ensuring robust and dynamic interpretations of the past.